In a small bowl, stir the cornstarch into 1 Tbs. of the chicken broth until smooth. Stir in the remaining 5 Tbs. broth, along with the ponzu and sesame oil.
Season the sliced beef with 1/2 tsp. salt and several grinds of pepper. Heat 2 Tbs. of the oil in a large skillet or stir-fry pan over medi...